1. Field of the Invention
The present invention relates to a stripping solution for photolithography which can be suitably used in manufacture of semiconductor elements such as IC and LSI and liquid crystal panel elements and to a method for forming a pattern using the same.
2. Related Art
When semiconductor elements such as IC and LSI or liquid crystal panel elements are manufactured, a CVD vapor-deposited metal film or an insulating film such as an SiO2 film is first formed on a substrate such as a silicon wafer and glass. Subsequently, a photoresist composition is uniformly applied on the metal film or insulating film to form a photoresist film, and this photoresist film is selectively exposed and developed to form a photoresist pattern. Then, the substrate is subjected to an etching treatment using this photoresist pattern as a mask to form a fine circuit. Thereafter, the photoresist pattern is ashed, and residual materials of the ashed photoresist pattern and etching residual materials are stripped away using a stripping solution for photolithography.
It is to be noted that aluminum (Al); an aluminum alloy (Al alloy) such as aluminum-silicon (Al—Si), aluminum-copper (Al—Cu), and aluminum-silicon-copper (Al—Si—Cu); titanium (Ti); a titanium alloy (Ti alloy) such as titanium nitride (TiN) and titanium tungsten (TiW); tantalum (Ta); tantalum nitride (TaN); tungsten (W); tungsten nitride (WN); copper (Cu); or the like may be used as the above-described metal film. In addition, an SiO2 film is often used as the insulating film. The metal film and insulating film are formed as a single layer or a plurality of layers on the substrate.
The stripping solution for photolithography is desired to be able to effectively strip away residual materials of a photoresist pattern and etching residual materials and to have excellent anticorrosion properties on metals. In order to achieve both of the performances, use of hydrofluoric acid and a compound containing ammonia as a counter amine thereof (see Patent Documents 1 to 3), hydrofluoric acid and a compound using 1,8-diazabicyclo[5.4.0]undecene-7 as a counter amine thereof (see Patent Document 4), or the like has been proposed so far.    Patent Document 1: Japanese Unexamined Patent Application, Publication No. 2001-83713    Patent Document 2: Japanese Unexamined Patent Application, Publication No. H9-197681    Patent Document 3: Japanese Unexamined Patent Application, Publication No. 2000-47401    Patent Document 4: Japanese Unexamined Patent Application, Publication No. 2000-181083